DS3610 Enters Clinical Development in Patients with Advanced Solid Tumors as First STING Agonist ADC in Industry-Leading ADC Portfolio of Daiichi Sankyo

TOKYO & BASKING RIDGE, N.J.--(BUSINESS WIRE)--The first patient has been dosed in a first-in-human phase 1 trial evaluating DS3610 in patients with advanced, metastatic or unresectable solid tumors.

DS3610 is an investigational STING agonist antibody drug conjugate (ADC) containing an immunomodulatory payload discovered by Daiichi Sankyo (TSE:4568).

Despite the availability of various cancer immunotherapies, there remains an unmet need for novel treatment options with distinct mechanisms of action that may overcome resistance to current immunotherapy, enhance tumor responses and delay disease progression in solid tumors.

“By combining precise tumor targeting with an immunotherapy payload, Daiichi Sankyo is exploring a new way to harness the body’s own defenses to attack cancer,” said Ken Takeshita, MD, Global Head, R&D, Daiichi Sankyo. “The initiation of this first-in-human trial of DS3610 represents an important step forward in advancing the next wave of our antibody drug conjugate portfolio and reaffirms our commitment to creating transformative medicines for patients with cancer.”

About the Phase 1 Trial
The multicenter, open-label, first-in-human phase 1 trial will assess the safety, tolerability, preliminary efficacy and pharmacokinetics of DS3610 in patients with advanced, metastatic or unresectable solid tumors for which no additional standard therapy is available. The dose escalation trial will assess the safety and tolerability of increasing doses of DS3610 to determine the recommended doses for expansion in patients with advanced, metastatic or unresectable solid tumors.

The trial will evaluate safety endpoints including dose-limiting toxicities and adverse events. Pharmacokinetic and immunogenicity endpoints will also be assessed, as well as exploratory efficacy endpoints including objective response rate, disease control rate, duration of response, time to response, progression-free survival and overall survival.

The trial is expected to enroll patients across multiple sites globally, including Asia, Europe and North America. For more information, please visit ClinicalTrials.gov.

About DS3610
DS3610 is an investigational STING agonist ADC consisting of a monoclonal antibody with novel Fc modifications attached to an immunomodulatory payload that acts as an agonist of a stimulator of interferon genes (STING). DS3610 delivers a STING agonist payload directly to tumor environments and induces the immune system in the body to target cancer cells.

About the ADC Portfolio of Daiichi Sankyo
The Daiichi Sankyo ADC portfolio consists of eight ADCs in clinical development crafted from ADC technology discovered in-house by Daiichi Sankyo.

The DXd ADC Technology platform of Daiichi Sankyo consists of six ADCs in clinical development where each ADC is comprised of a monoclonal antibody attached to a number of topoisomerase I inhibitor payloads (an exatecan derivative, DXd) via tetrapeptide-based cleavable linkers. The DXd ADCs include ENHERTU^® and DATROWAY^®, which are being jointly developed and commercialized globally with AstraZeneca, and ifinatamab deruxtecan (I-DXd), raludotatug deruxtecan (R-DXd) and patritumab deruxtecan (HER3-DXd), which are being jointly developed and commercialized globally with Merck & Co., Inc, Rahway, NJ, USA. DS-3939 is being developed by Daiichi Sankyo.

Additional ADCs being developed by Daiichi Sankyo include DS-9606, which consists of a monoclonal antibody attached to a modified pyrrolobenzodiazepine (PBD) payload and DS3610, which consists of an antibody attached to a novel immunomodulatory payload that acts as an agonist of STING.

Ifinatamab deruxtecan, patritumab deruxtecan, raludotatug deruxtecan, DS-3939, DS-9606 and DS3610 are investigational medicines that have not been approved for any indication in any country. Safety and efficacy have not been established.

About Daiichi Sankyo
Daiichi Sankyo is an innovative global healthcare company contributing to the sustainable development of society that discovers, develops and delivers new standards of care to enrich the quality of life around the world. With more than 120 years of experience, Daiichi Sankyo leverages its world-class science and technology to create new modalities and innovative medicines for people with cancer, cardiovascular and other diseases with high unmet medical need. For more information, please visit www.daiichisankyo.com.